Remove tensioner, unbolt the cam sprocket, rotate engine forward to TDC, move cam sprocket however many teeth it takes to line up, replace cam sprocket, replace tensioner, check IP timing. If I counted correctly the sprocket has 36 teeth which means a one tooth jump is 10 cam degrees and 20 crank degrees. I'm guessing that maybe the tensioner is weak or one of the check balls got stuck and it depressuized temporarily which allowed the timing chain to jump.

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'82 300D - Light Ivory, 2nd Owner (Back in the wind April 2013!)

'95 E300D - White, grey interior. (Suffering from stuck/broken glow plugs)

Deuteronomy 22:4-
"Thou shalt not see thy brother's ass or his ox fall down by the way, and hide thyself from them: thou shalt surely help him to lift them up again."